The Dickinson press., 1887-04-30
ABOUT ALUMINIUM.
AN INTERESTING ACCOUNT OF ITS
REMARKABLE PROPERTIES.

As Malleablc as Gold or Silver and Moro
Durablc-Its Value In the Ago of Elec-
tricity-Rcsistanco to OCorrosion.StronS-
er Than Steel.
OF course the reader readily understands
that aluminium does not occur in nature in
metallic form, and the great secret is to iso-
late it from the substances with which it up
pears and reduce it to the metallic state. Tho
word means the metal of clay. AS fact,
however, clay soil comes from the metal base,
not the metal from tie SOIL Combined with
oxygen, in one form or another, it forms
mountain masses and is the base of vast
amount of common carths. BY the action of
Dir and water the aluminium compound is de-
composed tho alkali washed away and clay
soil is loft. We have then to consider the sur
face of the tillable earth Us very largely tho
result of the decomposition of this metal
leaving porous substance, which we culti-
vate and i'll which we grow our vegetable pro-
ducts. The compound forms of aluminium
are far from uniform, and include mica, field
spar, porplyry, ruby, sapphire, garnet, tur-
quoi>c, bcauxite and cryolitc. The last two
compounds are commonly those used for OK
tracing the pure metal But in America cor
undum, which is found i'll North Carolina, is
and probably will be the main source of
supply.
OF course the general reader whatever his
interest In this remarkable substance, will
not understand the chemical processes of OK
traction. 1t is far moro interesting to learn
as much as possible of its physical properties.
Its color is beautiful silvcry white, with u
very slight blush tint. When cut it resembles
piece of tin freshly cut. 1t is o,lor"ss and
tascless when absolutely pure 1t is fully as
malleablc as gold and silver, and can be beaten
into leaves that can be used MS silver and gold
leaf are; they arr" however, far more durable
1t can be drawn out into exceedingly fine
wire. Its elasticity is TINT of silver, and its
tanarity the same, but by lamlncrins it bc-
comes as hard rs iron AMI rs elastic. y bar
three feet long and n quarter of an inch
square, subjected to tests, was found to llilve
tensile strength of twelve tons to the square
inch. Taking its strength i'll relation to its
weight, it compares with steel of thirty-tivc
tons per square inch tensile strength.
OTHER PROPERTIES
| Aluminium is also remarkably sonorous;
so that when bar in suspension is struck i.
gives q sound of u crystal bell. 1t mcts ut e
temperature higher than zinc and lower than,
silver, and is therefore to be ranked rs easily
fusiblc. AT any temperature whatever it re-
mains fixed: that is it loses mono OF its weight.
| II conducts electricity with great facility
/ eight times better than iron and twice better
/ than copper. 1t also ranks very high, better
than copper and silver, Us n conductor of
heat. These facts suggest the possible and
/ prabablc value of aluminium i'll the age of
elcctricity--its value III connection with our
new motor.
But still more remarkable are the proper
! ties of this metal in resisting corrosion. The
air has 10 effect on it whatever, whether
moist or dry; neither have sulphur fumes.
/ Nor does pure oxygen affect it, whether cold
or hot, although if brought into white heat
it burns, producing a strong light. Neither
has water power to corrode it at any ordi-
nary heat, but at 100 deg. it slowly decom-
poses the water. 1t is equally true that such
destructive gases as sulphurettcd hydrogen
do not affect it; and tho acils, such as sui
phuric and nitric, do not affect aluminium to
any perccptible degree, and hydrochloric acid
acts very slowly on the puro metal. This
is why it was used for the peak of the Wash
ington monument, being klcorrodiblo prac
tically where other metals would be eaten VI
by the atmosphere and rains.
CoRRoDED BY ALKALIEs
But alkalics, on the contrary, as potash
soda and limo, act on aluminium very easily
driving Off the hydrogen and leaving cal
cium or other compond. So, also, chlorine
iodine, bronlinc and fuorinc attac, the meta
at once and break it up rapidly. Its power
to resist acids makes it exceedingly useful il
diseases where tubes Of metal must be used
since sweat and rurulcnt matter cannot
alter it.
Such is the nature Of this metal of tn,
future, sketchcd as we'll as may be withou
introducing technical language The worl,
contains IL thousand times as much Of it as i
does of iron. Its strength surpasses both irol
and steel. while it is almost absolutely incor
robbie. Glass, acids, air and water do no
tarnish it; nor does heat change its weight o
color. 1t is the best known conductor O
heat and electricity. 1t is lighter than some
of our hardest woods, and is worked will
great ease. In tho words of n leading scicil
tist: at is the lightest, easiest worked
strongest, most durable and generally mos
valuable of all metals; and tho man who in
vents a method of making it cheaply will re
volutionizc industry" 1t is not easy t.
imagine the universal and sweeping influence
OF the introduction of two such metals n
aluminium and malleable glass into our in
dustrial economy in single generation
Globe-Democrat.